(a) Field
The present inventive concept relates to a liquid crystal display device and a method of driving the same.
(b) Description of the Related Art
A liquid crystal display device, which is one of flat panel display devices that are currently used widely, includes a lower display panel, on which a plurality of pixel electrodes are formed, an upper display panel, on which a common electrode is formed, and a liquid crystal layer interposed between the two display panels, and a predetermined voltage is applied to the plurality of pixel electrodes and the common electrode to realign liquid crystal molecules of the liquid crystal layer to thereby adjust an amount of transmitted light.
According to a mode of the liquid crystal display device, a common electrode may be formed on a lower display panel in addition to a plurality of pixel electrodes so as to adjust alignment of liquid crystal molecules by using a fringe field.
The liquid crystal display device may be configured to sense a touch of a user by including a touch sensor.
A touch sensor may be classified, according to various methods, into a resistive type touch sensor, a capacitive type touch sensor, an electro-magnetic (EM) type touch sensor, an optical type touch sensor or the like.
In the liquid crystal display device, a touch screen panel (TSP) that is separate from a display panel may be formed and adhered to the display panel, or a TSP and a display panel may be integrally formed with each other.
Examples of an integral structure are an on-cell type structure and an in-cell type structure and the like.
According to development of the technology of display manufacture, display panels are becoming thin and a distance between a sensing electrode used to sense a touch of a user and other electrodes is shortened.
In particular, as a distance between a sensing electrode in a touch screen panel and a common electrode in a display panel is shortened, parasitic capacitance which is undesirable is formed between the two electrodes and affects voltages of the respective electrodes.
According to the conventional art, a voltage of a common electrode according to a mode of driving the display panel may affect a voltage of the sensing electrode, and problems may be caused in sensing a touch of a user.
However, in contrast, as a voltage of a touch driving signal supplied to the sensing electrode has been recently increased (e.g., a voltage of 8 V or higher), the voltage of the sensing electrode rather affects the voltage of the common electrode to affect screen display of a display device.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the inventive concept and therefore it may contain information that does not form the prior art.